package com.example.demo.config;

import java.util.concurrent.ThreadPoolExecutor;

import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.scheduling.annotation.EnableAsync;
import org.springframework.scheduling.concurrent.ThreadPoolTaskExecutor;

@Configuration
@EnableAsync
public class GlobalConfig {

	private static final int corePoolSize = 16;       		// 核心线程数（默认线程数）
	private static final int maxPoolSize = 300;			    // 最大线程数
	private static final int keepAliveTime = 60;			// 允许线程空闲时间（单位：默认为秒）
	private static final int queueCapacity = 200;			// 缓冲队列数
	private static final String threadNamePrefix = "Async-Service-"; // 线程池名前缀
	
	@Bean("taskExecutor")
	public ThreadPoolTaskExecutor defaultThreadPool() {
		ThreadPoolTaskExecutor executor = new ThreadPoolTaskExecutor();
		executor.setCorePoolSize(corePoolSize);   
		executor.setMaxPoolSize(maxPoolSize);
		executor.setQueueCapacity(queueCapacity);
		executor.setKeepAliveSeconds(keepAliveTime);
		executor.setThreadNamePrefix(threadNamePrefix);
		
		// 线程池对拒绝任务的处理策略
		executor.setRejectedExecutionHandler(new ThreadPoolExecutor.CallerRunsPolicy());
		// 初始化
		executor.initialize();
	    return executor;
	}
}
